As the series progresses, a vast government project emerges. Known as "Northern Lights", it revolves around the development and use of the Machine. It is headed by a mysterious figure known only as "Control", an unnamed official who deploys teams of Intelligence Support Activity (ISA) operatives who are identified by the Machine using a blue box; classified as "assets", they have no knowledge of the Machine,Person of Interest Seasons 1-5 but work within its own parameters. They are used to eliminate perceived terrorist threats on the recommendation of a department known as "Research". "Control" also used the team to eliminate key personnel who are aware of the Machine's existence. In the third season, Control physically makes her first appearance, and the organization Vigilance exposes the government's Northern Lights program to the public,Person of Interest Seasons 1-5 DVD forcing Control to shut it down. The private technology firm Decima Technologies steals Samaritan, a creation of Finch's MIT classmate Arthur Claypool that is similar to the Machine, and plans to use it against the Machine.